The estimated prevalence of depression or depressive symptoms was 28.8% among residents and interns worldwide in a meta-analysis of 54 studies of the issue, according to a report published online December 8 in JAMA.
The depression rate ranged from 20.9% to 43.2%, depending on the instrument used to assess symptoms. Eleven studies used the Beck Depression Inventory (BDI), 11 used the Center for Epidemiological Studies Depression Scale (CES-D), 8 used the two-item Primary Care Evaluation of Mental Disorders questionnaire (PRIME-MD), 7 used the nine-item Patient Health Questionnaire (PHQ-9), 4 used the Zung Self-Rating Depression Scale (SDS), 3 used the Harvard Department of Psychiatry/National Depression Screening Day Scale (HANDS), and 11 used other validated methods, said Dr. Douglas A. Mata of the department of pathology, Brigham and Women’s Hospital and Harvard Medical School, Boston, and his associates.
“It is important to note that the vast majority of participants were assessed through self-report inventories that measured depressive symptoms, rather than gold-standard diagnostic clinical interviews for major depressive disorder,” they said.
The meta-analysis included 31 cross-sectional and 23 longitudinal studies published in peer-reviewed journals since 1963 and involving 17,560 residents or interns in North America (35 studies), Asia (9 studies), Europe (5 studies), South America (4 studies), and Africa (1 study). When the results were pooled, the overall prevalence of depression or depressive symptoms was 28.8% (4,969 of 17,560 participants).
In a sensitivity analysis, no individual study affected the overall prevalence estimate by more than 1%. Further analyses showed no significant differences in the prevalence of depression between cross-sectional and longitudinal studies, between U.S. studies and those performed in other countries, between studies of nonsurgical residents only vs. studies of all types of residents, or between studies of interns only vs. studies of upper level residents only. This suggests that the underlying causes of depressive symptoms “are common to the residency experience,” Dr. Mata and his associates said (JAMA. 2015 Dec 8. doi: 10.1001/jama.2015.15845).
The prevalence of depression increased over time. Although this rise was characterized as modest, “it is notable, given efforts by the Accreditation Council for Graduate Medical Education, European Working Time Directive, and others to limit trainee duty hours and improve work conditions. [This] trend may reflect the medical community’s increased awareness of depression or developments external to medical education. Future studies should explore specific factors that may explain this trend,” the investigators said.
The study findings indicate that the long-term health of physicians may be affected, since depression has been linked to a higher risk of future depressive episodes and greater long-term morbidity. Patient care may also be affected, given the established association between physician depression and lower-quality care, they added.